Revert^2 Integrate transaction tracing with perfetto
Define the perfetto custom data source TransactionDataSource.
TransactionDataSource is registered with perfetto and is used
to listen to perfetto events (setup, start, stop, flush)
and to write trace packets to perfetto.
The user can configure/start/stop tracing via /system/bin/perfetto.
Tracing can operate in the following modes.
ACTIVE mode:
The transactions ring buffer (starting state + following committed
transactions) is written (only once) to perfetto when the 'start'
event is received.
Transactions are then written to perfetto each time they are committed.
On the receiver side, the data source is to be configured to periodically
flush data to disk providing a virtually infinite storage.
CONTINUOUS mode:
Listens to the perfetto 'flush' event (e.g. when a bugreport is taken).
When a 'flush' event is received, the ring buffer (starting state + following
committed transactions) hold by TransactionTracing is written to perfetto.
On the receiver side, the data source is to be configured with a dedicated
buffer large enough to store all the flushed data.
Bug: b/284424784
Test: atest libsurfaceflinger_unittest && atest transactiontrace_testsuite
Change-Id: I703ed53e71f442e2f6af7c4a638d2f847107167a
diff --git a/services/surfaceflinger/Tracing/TransactionDataSource.cpp b/services/surfaceflinger/Tracing/TransactionDataSource.cpp
new file mode 100644
index 0000000..05b89b8
--- /dev/null
+++ b/services/surfaceflinger/Tracing/TransactionDataSource.cpp
@@ -0,0 +1,82 @@
+/*
+ * Copyright 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "TransactionDataSource.h"
+#include "TransactionTracing.h"
+
+#undef LOG_TAG
+#define LOG_TAG "TransactionTracing"
+
+#include <log/log.h>
+
+namespace android {
+
+void TransactionDataSource::Initialize(TransactionTracing& transactionTracing) {
+ mTransactionTracing.store(&transactionTracing);
+
+ auto args = perfetto::TracingInitArgs{};
+ args.backends = perfetto::kSystemBackend;
+ perfetto::Tracing::Initialize(args);
+
+ perfetto::DataSourceDescriptor descriptor;
+ descriptor.set_name(kName);
+ TransactionDataSource::Register(descriptor);
+}
+
+void TransactionDataSource::UnregisterTransactionTracing() {
+ mTransactionTracing.store(nullptr);
+}
+
+void TransactionDataSource::OnSetup(const TransactionDataSource::SetupArgs& args) {
+ const auto configRaw = args.config->surfaceflinger_transactions_config_raw();
+ const auto config =
+ perfetto::protos::pbzero::SurfaceFlingerTransactionsConfig::Decoder{configRaw};
+
+ if (config.has_mode() && config.mode() != TransactionTracing::Mode::MODE_UNSPECIFIED) {
+ mMode = static_cast<TransactionTracing::Mode>(config.mode());
+ } else {
+ mMode = TransactionTracing::Mode::MODE_CONTINUOUS;
+ ALOGV("Received config with unspecified 'mode'. Using 'CONTINUOUS' as default");
+ }
+}
+
+void TransactionDataSource::OnStart(const StartArgs&) {
+ ALOGV("Received OnStart event");
+ if (auto* p = mTransactionTracing.load()) {
+ p->onStart(mMode);
+ }
+}
+
+void TransactionDataSource::OnFlush(const FlushArgs&) {
+ ALOGV("Received OnFlush event");
+ if (auto* p = mTransactionTracing.load()) {
+ p->onFlush(mMode);
+ }
+}
+
+void TransactionDataSource::OnStop(const StopArgs&) {
+ ALOGV("Received OnStop event");
+}
+
+TransactionTracing::Mode TransactionDataSource::GetMode() const {
+ return mMode;
+}
+
+std::atomic<TransactionTracing*> TransactionDataSource::mTransactionTracing = nullptr;
+
+} // namespace android
+
+PERFETTO_DEFINE_DATA_SOURCE_STATIC_MEMBERS(android::TransactionDataSource);